Mysteries of the Universe

How much of our universe do we know?

Public science engagements have been the fuel that drives my love for astronomy. Whenever I have astronomy-related public engagements these are some of the questions I often get: Is there life out there? What is the fate of our universe? How was the universe formed? In this blog, I am to tackle these questions and give a brief overview of the universe as we know it.

The longest presiding theory of how the universe formed is The Big Bang Theory (no Sheldon is not part of it); According to this theory, 13.8 billion years ago the universe was just a single point (singularity) an explosion occurred (‘big bang’) and the universe started expanding. This period of rapid expansion (inflation) lasted for a short moment, as the expansion slowed down the temperature decreased to a point where basic building blocks of particles started forming (nucleosynthesis). This epoch was followed by a phase where the universe was a dense plasma (Cosmic Microwave Background) the remnants of this plasma are still visible today and can be observed using radio telescopes (e.g. ACT; PLANCK). As the universe continued expanding clumps of matter were pulled by gravity and stars were birthed. As more matter accreted larger structures started forming; first galaxies, then clusters of galaxies and these structure formations evolved to the universe we have today.


The Lambda Cold Dark Matter (LCDM) model is the mathematical representation of the Big Bang theory. Lambda (Λ) is the cosmological constant which was used by Einstein to compute his theory of general relativity; it is related to dark energy (which could be understood as a force that pulls things apart, causing the universe to expand). Cold dark matter is deferent to the normal matter (baryonic) as it does not emit light (‘photons’) but its existence is proved through its gravitational effects. According to this model, the universe is constituted of 68% dark energy, 27% dark matter and 5% ‘normal’ matter. So, all the stars you see at night and the billions of galaxies that have been observed only make up 5% of the universe! Using the LCDM model we can also predict the fate of our universe; currently, cosmologists believe that our universe is ‘flat’, hence, it will continue expanding forever and eventually the universe will be a cold frozen place. No need to worry though, it won’t happen any time soon (soon being billion years scale).

Although the Big Bang theory and the LCDM model explain the bulk of the observable universe, it has been adapted to further explain the physical phenomenon that we observe today (e.g. The Oscillating Universe Theory).

The curious mind never rests! So now that we have a clearer idea of the origins of the universe more questions pop up. One of the prominent questions is: Are we alone in the universe? I believe not, but of course, we have to back our beliefs with scientific evidence. There are two main approaches to answering this question; searching for earth-like planets and awaiting signals from aliens.

Kepler, a NASA space telescope is on a mission to locate planets that are in the habitable zone which could sustain life. To date, Kepler has detected 4164 exoplanets and recently it was reported that the most earth-like planet was discovered by the Kepler mission. This exoplanet orbits a star similar to our sun, it’s 1.06 times bigger and receives 75% of the sunlight that Earth receives from the sun. As exciting as it may sound, this planet is 300 light-years away from us; this means that if we were able to travel at the speed of light, it would take us 300 years to reach this planet. So please take care of our planet, we have no alternative home!

The SETI Institute, on the other hand, aims to use radio telescopes to ‘listen’ to extraterrestrial intelligent life. Their strategy is to search for narrow-band radio transmissions that come from outside our solar system, these transmissions would indicate extraterrestrial technological advancement and signal the possibility of intelligent life outside our solar system. A SETI Institute researcher once presented at a conference I was attending, a student asked: ‘So if we do eventually find aliens, what’s the plan?’. The presenter didn’t quite answer the question, my only hope is that they would be kinder than humans.

Astronomy is an exciting field because it is continuously evolving. With the majority of the Square Kilometre Array (SKA) being hosted by South Africa, there has never been a better time for young students to hop on the astronomy bandwagon. The SKA project will require expertise from various fields such as; Engineering, Artisan, Computer Science etc. The beauty of astronomy is that it doesn’t box one to a particular set of skills but instead exposes one to various fields.

The ultimate ‘cherry on top’ is that although many questions have been answered, many more are yet to be asked. Sometimes it takes decades to answer one question (e.g. the existence of gravitational waves) and at times the discovery of one phenomenon raises a thousand more questions (e.g. Fast Radio Bursts). So if you, like me, are always on a quest for problems to solve; then astronomy will be equally fascinating for you.

A Passionate Nation

What does the youth of 1976 have in common with today’s youth?

As we commemorate Youth month and specifically Youth Day on the 16th of June, I have been trying to search for similarities between the youth of 1976 and the youth of today. The students that led the march against the Bantu education policy must have been extremely courageous and passionate. They knew that their actions would result in severe consequences, yet they still soldiered on. The repercussions of their actions lead to some of the educational privileges African pupils have today.

Even though the older generation has labelled us as the ‘doomed generation’, the passion of the historic Soweto Uprising generation still strongly drives the youth of today. You can see it in the artistic videos that are shared in social media, the faces of our national sports team players, and the students and rise against all odds and excel in (previously exclusive) academic fields such as science. Although sometimes misdirected, passion is alive within us and will drive us to greater victory.

In this blog, I will share stories of young South Africans that truly inspire me and give us a glimpse of the South Africa we can become if passion is harnessed and maximised.

Earlier this year I was invited to the Spirit of light event, hosted by the renowned mama Gcina Mhlophe; I was pleasantly surprised when I found out that I would be sharing the podium with Major Mandisa Mfeka. I had read much about her and watched her documentary; her story was truly inspiring. She radiated passion as she narrated her story that night. A young girl from the township of Ntuzuma in KZN who fell in love with airplanes as a result of frequent visits to the Virginia airport in Durban.

In 2008 she joined the  SAAF and was enrolled at Central Flying School in Langebaan, Western Cape, in 2010, going on to get her wings in 2011. Early in 2019, she became South Africa’s first black female fighter pilot and in May, she was one of the pilots who flew at President Cyril Ramaphosa’s inauguration. Her tagline is ‘the sky is the baseline’, indeed her passion defied all circumstances and launched her in the sky. 

As an astronomy fanatic, I had always fancied having a celestial body named after me, even if it was a mere shooting star (Meteor). Hence, when I heard about a minor planet named after a young science enthusiast, Siyabulela Xuza, I was instantly intrigued by his work. Xuza, born in Mthatha Eastern Cape, is an energy-engineering expert and entrepreneur with a passion for clean affordable energy.

At the age of 16, propelled by passion, Siyabulela Xuza began experimenting with rocket fuel he made in his mother’s kitchen. After numerous failed launches, his experiments lead him to launch a homemade rocket, The Phoenix, which achieved an altitude of over 1 kilometre. This earned him the junior South African amateur high-powered altitude record. Xuza’s project on solid rocket fuel won gold at the Eskom Expo for Young Scientists in 2006, along with the Dr Derek Gray Memorial Award for the most prestigious project in the country. In 2007, his other brainchild, “African Space: Fueling Africa’s quest to space”, was entered into the International Science and Engineering Fair where it won the “Best of Category” award and a “First Award” in the energy and transportation sector. His work has earned him several leadership positions and awards, including a scholarship to the Harvard School of Engineering and Applied Sciences.

I often get a glimpse of how passionate young South Africans are when I attend career exhibitions. Earlier this year I was part of a team of UKZN staff and students that attended the KZN High Achievers Seminar which was co-hosted by UKZN and the KZN department of education. At this seminar, top achieving learners from schools ranked quantile 1-3 were invited to listen to career talks. During the exhibition, two particular students approached my stand and started asking questions about astronomy and career opportunities. They passionately shared their love for astrophysics and started asking questions about wormholes and space-time dynamics. I was fascinated with the level of knowledge they possessed regardless of the shortage of facilities in their schools. I am certain that these learners, given the support and opportunities, will become the next Einsteins. This conversation left me beaming with pride, indeed, with these kinds of minds our future is in safe hands.

These stories are a testimony of the depth of passion in our youth and how, if cultivated and harnessed, it can significantly transform our nation. ‘Inkunzi isematholeni’; directly translated this isiZulu proverb means that the bull is among the calves. Indeed, the future of this nation is in the hands of the youth; hence, as a community, we need to synchronise our efforts to ensure that the young generation lives to its full potential. This will require the parents to be fully aware of their children’s talents and support them unreservedly, for teachers to impart their knowledge gracefully, and for the government to create a conducive environment for these young minds to flourish.